Toilet rim block and rim block cage

ABSTRACT

A toilet rim block which consists of an outer cover and a core, and to a rim block cage including the toilet rim block. The outer cover includes a first composition and the core includes a second composition. Preferably, the first and the second compositions differ from each other by at least one of the following features: different active substances, different concentration but same active substance, and different viscosity. The outer cover partly encloses the core and the core protrudes on at least one face of the toilet rim block right to the surface as a pole and is exposed. The core is shaped such that the surface of the exposed area changes upon even wear of the surface of the toilet rim block, the surface of the exposed area of the core reducing upon even wear of the surface of the toilet rim block.

FIELD OF THE INVENTION

The present invention is in the field of toilet rim blocks and relatesto a toilet rim block that consists of at least one mass and a core. Theinvention also relates to a rim block cage comprising a toilet rim blockaccording to the invention.

BACKGROUND OF THE INVENTION

Toilet rim blocks comprising two masses are known, for example fromEP0791047 B1. A toilet rim block is described therein, in which one massis surrounded at least in part by a further mass. Since both massescomprise the same active ingredient in different concentrations, uponrinsing and complete transition to the inner mass, there is a change inthe concentration of the active ingredient. However, this change issudden, and a continuous change is not possible using this technologywithout significant effort.

DE 102008028138 A1 discloses coated toilet rim blocks, in which thecompositions of the toilet rim block and the coating thereof areseparated. When first used, e.g. at the time of the first flush, noactive ingredient is dispensed from the toilet rim block into theflushing water, but rather from the coating of said block. It is thuspossible to adjust optical properties of the toilet rim block.Furthermore, WO 2010018006 proposes coating the toilet rim blocks inorder to adjust optical properties.

WO 2006070209 discloses cylindrical toilet rim blocks that comprise acore. Said blocks are used mainly as in-tank cleansing blocks and areintended to be permanently in water.

WO 2012062914 describes multilayer toilet rim blocks, in which thedifferent layers can have different effects.

An essential feature of the embodiments known from the prior art is thatthe transition between the layers is sudden, in particular when thetransition is intended to be an indicator of consumption. No solutionhas yet been found for achieving a continuous change in the dispensingof the active ingredient.

BRIEF SUMMARY OF THE INVENTION

This problem is solved by a toilet rim block as described herein. Thepresent invention relates to a toilet rim block that consists of atleast a casing and a core. The casing comprises a first composition andthe core comprises a second composition. The first and the secondcomposition preferably differ by at least one of the following features:different active ingredients, different concentration of the same activeingredient, or a different viscosity. The casing surrounds the core massin part. The core projects, on at least one side of the toilet rimblock, as a pole as far as the surface of the toilet rim block, and isthus exposed. Preferably, the profile of the core in the toilet rimblock is such that the surface of the exposed face changes with uniformwear of the surface of the toilet rim block.

In this case, it is possible to dispense active ingredients into theflush simultaneously from the casing and from the core from the verystart and in conjunction with a very wide variety of geometricalexternal shapes of the toilet rim block. In this case, the dispensingratio of active ingredients from the casing and from the core can bespecifically adjusted to the number of flushes. In particular, thedispensing ratio can be adjusted such that it can change continuouslywith the number of flushes. The change is preferably continuous.

Preferably, the initial situation on the undissolved toilet rim block isdecisive for the change in the surface of the exposed face of the coreand thus for the change in the active ingredient composition dispensedinto the flush in each case. In other words, the initial situation is,preferably, the undissolved toilet rim block in the unused originalstate. Within the meaning of the invention, “exposed” means the baresurface.

Outer, for example full-surface, coatings of the toilet rim block whichprovide the unused toilet rim block with a shine for example canadditionally be provided. Coatings of this kind are usually very thin,and therefore dissolve in the first flushes, preferably even in thefirst 3 flushes, particularly preferably even in the first flush.Accordingly, active ingredients actually begin to be dispensed into theflushing water only after said outer coating has dissolved. Therefore,for the purpose of the present invention, the initial situation for theundissolved toilet rim block is understood to be the toilet rim blockwithout said outer coating.

In a particularly preferred embodiment of the invention, the surface ofthe exposed face of the core reduces with uniform wear of the surface ofthe toilet rim block. This makes it possible, for example, to reduce thedispensing of an active ingredient that is to be dispensed from the corein such a way that a user can perceive the reduction as an indicator ofconsumption.

Viewed from outside the preferably spherical toilet rim block andtowards the center of the toilet rim block, the core preferably forms acone, or at least a truncated cone, having concave walls, the base ofthe cone being a geometric shape that is projected onto the outer faceof the toilet rim block, preferably the spherical surface thereof, whichshape is preferably the projection of a circle, an ellipse, a polygon ora shape that differs slightly therefrom.

For the undissolved toilet rim block, the area ratio of the exposedsurface of the core to the exposed surface of the casing is preferablybetween 5% and 67%, particularly preferably between 10% and 38%.

It is also possible, but less preferable, for the toilet rim block to betotally covered by the core (99%-100% coverage) or by the casing in theunused original state of the toilet rim block. Specifically, the totalcoverage means that initially only one composition can be dispensed whenthe toilet rim block is undissolved.

After the toilet rim block has been partially used, the area ratio ofthe exposed surface of the core to the exposed surface of the casing ispreferably between 1:3 and 1:1

It is furthermore preferable for the toilet rim block to comprise asecond pole that projects to the surface on the side of the toilet rimblock opposite the first pole, and is thus exposed.

Preferably at least one, preferably the central, core portion is formedas a cylindrical segment. In particular for two-pole toilet rim blocks,the core can be produced having a distribution that is substantiallysymmetrical with respect to the two poles, provided that the centralportion is cylindrical.

It is also preferable for the first pole and the second pole to beconnected by a strand. It is preferable for the core to be integral.This results in a better time variation of the dispensing of the activeingredient as the toilet rim block is consumed.

In the case of two-pole toilet rim blocks, in particular those that areconnected by a strand, it is preferable for the cross-sectional profileof the core to have a cross-sectional reduction between the first poleand the second pole.

According to a preferred embodiment of the invention, in particular incombination with two-pole toilet rim blocks, the casing surrounds thecore in an annular manner. The core can thus extend through the centerof the ring and open out on each side as the first and second pole.

The toilet rim block is preferably spherical. The sphericity isparticularly between 0.8 and 1, i.e. substantially ball-shaped,particularly preferably between 0.85 and 1 and very particularlypreferably between 0.9 and 1. According to a particularly preferredembodiment of the invention, a rim block cage comprises at least 2,preferably at least 3, spherical toilet rim blocks that are arranged ina row, it being further preferable for the poles of the toilet rimblocks to be arranged randomly. Random arrangement means that the toiletrim blocks included in the toilet rim block arrangement have differentpole orientations. A rim block cage of this kind can be produced morecost-effectively since it is not necessary to orient the toilet rimblocks in advance. It has been found that spherical toilet rim blocksaccording to the invention mean that orientation in advance is notnecessary in order to produce the desired dispensing ratio to the numberof flushes. Of course, the toilet rim blocks can also be oriented, if aspecific aesthetic form is desired, in particular if the core and thecasing are different colors.

The sphericity Ψ of a body K is the ratio of the surface of the body tothe surface of a ball of the same volume:

${\Psi = \frac{{\pi^{\frac{1}{3}}\left( {6V_{p}} \right)}^{\frac{2}{3}}}{A_{p}}},$

where Vp is the volume of the body and Ap is the surface of said body.

The almost ideal spherical shape of the toilet rim block achievesuniform rinsing of the toilet cleansing block such that the toilet rimblock substantially maintains its ball shape even during and/or afterthe rinsing processes and corresponding wear of the toilet cleansingblock.

The diameter of the spherical toilet rim block is preferably between 1mm and 10 cm, preferably between 5 mm and 5 cm, particularly preferablybetween 1 cm and 3 cm.

The invention further relates to an associated method for producing arotationally symmetrical toilet cleansing block, comprising the steps of

-   -   a) mixing the ingredients for the core composition, and mixing        the ingredients for the casing composition,    -   b) co-extruding the at least two mixtures,    -   c) cutting the extruded strand into portion pieces of a defined        mass,    -   d) shaping into rotationally symmetrical bodies such that the        core projects, on at least one side of the toilet rim block, as        a pole as far as the surface, and is thus exposed.

The shaping d) preferably takes place in a ball turning machine or in apress. A preferred ball turning machine is one comprising three rotatingsections or rolls in which the strand can be inserted, and the strand iscut by the roll sections and shaped into a ball by reducing the distancebetween the rolls. The desired final geometry according to the inventionis achieved by pressing the strand portion into a spherical space havingan identical volume.

Steps a) and b) can also be combined, i.e. mixing the ingredients in theextruder. The method steps may be carried out at different temperatures,and therefore heating or cooling steps may be interposed between thesteps. This is at the discretion of a person skilled in the art.

In a preferred embodiment, a further method step is carried out afterone of steps b) or c), in which the extruded strand is provided with alubricant. For this purpose, a sponge, in the form of a wheel, that ispermanently filled with the lubricant is guided over the extruded strandsuch that lubricant is applied to all or part of the surface, preferablyto between 10 and 40% thereof. In this case, adding the lubricantimproves the subsequent ball forming. Suitable lubricants are inparticular substances that are used for example as surfactants orrinsing regulators in formulations according to the invention. In thiscase, a lubricant selected from the group comprising dipropylene glycol,paraffins, non-ionic surfactants, polyethylene glycol and mixturesthereof, in particular dipropylene glycol, is particularly preferablyused.

The method for producing the rim block cage comprises steps a) to d)described above, and further comprises:

-   -   e) providing a plastics holder, preferably by means of an        injection molding process;    -   f) inserting the toilet rim block in the plastics holder;    -   g) closing the plastics holder.

Preferably, the toilet rim blocks are temporarily stored in a containerbetween steps d) and f). The container forms a kind of buffer, and it isthus possible to decouple the production of the toilet rim blocks fromthe production of the rim block cages. Preferably, the toilet rim blocksthat are used in the cages come from at least two containers, thecontainers having stored toilet rim blocks having differentcompositions. A rim block cage can thus be produced that can dispenseactive ingredients from different toilet rim blocks having differentcompositions.

Composition

The first and the second composition preferably differ at least byincluding different active ingredients and/or by a differentconcentration of the same active ingredient, the active ingredients inquestion being selected from the following list: perfume, surfactant(s),dyes, rinsing regulators, bleaching agents, builders, acid or base,antimicrobial active ingredients, polymers. Particularly preferably, theactive ingredients in question are selected from at least one of:perfume, surfactant(s), dyes. In the case of a toilet rim block in whichthe first and the second compositions differ by a differentconcentration of the same active ingredient, it is preferable for thecore to comprise a higher concentration of said active ingredient.Preferably, the higher concentration in the core is at least 0.5 wt. %greater than in the casing. Furthermore, it is preferable for the activeingredient in the core to have a concentration that is between at least1 wt. % and 10 wt. % higher than the concentration in the casing. Thewt. % specification is always in relation to the overall composition of100%. A concentration that is x wt. % higher means x percentage pointsmore.

The rim block cage according to the invention comprising a toilet rimblock can in addition be used in a method for cleaning and/orfragrancing and/or disinfecting flush toilets, such that the rim blockcage filled with the toilet rim block is hung in the toilet bowl and,when the toilet flush is actuated, dissolved ingredients of the toiletrim block enter the flushing water and can there have their cleaningand/or fragrancing and/or disinfecting effect. The invention thereforefurthermore relates to a method for cleaning and/or fragrancing and/ordisinfecting flush toilets using a rim block cage according to theinvention comprising a toilet rim block.

Substances that are also used as ingredients of cosmetic agents aredesignated in the following according to the International NomenclatureCosmetic Ingredient (INCI) as appropriate. Chemical compounds have anEnglish INCI designation, botanical ingredients are listed exclusivelyin Latin, in accordance with Linné, and what are known as common namessuch as “water”, “honey” or “sea salt” are also specified in Latin. TheINCI designations can be found in the International Cosmetic IngredientDictionary and Handbook—Seventh Edition (1997), which is published byThe Cosmetic, Toiletry, and Fragrance Association (CTFA), 1101 17thStreet, NW, Suite 300, Washington D.C. 20036, USA and contains over 9000INCI designations and references to over 37,000 trade names andtechnical names, including the associated distributors from over 31countries. The International Cosmetic Ingredient Dictionary and Handbookassigns the ingredients one or more chemical classes, for examplePolymeric Ethers, and one or more functions, for exampleSurfactants—Cleansing Agents, which it then explains in greater detailand to which reference may also subsequently be made.

The expression CAS means that the following numerical sequence is adesignation of the Chemical Abstracts Service.

In the scope of the present invention, unless otherwise stated, fattyacids and/or fatty alcohols and/or the derivatives thereof representbranched or unbranched carboxylic acids and/or alcohols and/or thederivatives thereof preferably having 6 to 22 carbon atoms, inparticular 8 to 20 carbon atoms, particularly preferably 10 to 18 carbonatoms, most preferably 12 to 16 carbon atoms, for example 12 to 14carbon atoms. The former are particularly preferred for ecologicalreasons, on account of the vegetable basis thereof, based on sustainableraw materials, but the teaching according to the invention is notrestricted thereto. In particular, the oxo alcohols and the derivativesthereof which can be obtained according to Roelen's oxo synthesis forexample and which preferably comprise 7 to 19 carbon atoms, inparticular 9 to 19 carbon atoms, particularly preferably 9 to 17 carbonatoms, most preferably 11 to 15 carbon atoms, for example 9 to 11, 12 to15 or 13 to 15 carbon atoms, can also be used correspondingly.

Perfume

The compositions preferably each include one or more fragrances,preferably in an amount of from 0.01 to 15 wt. %, in particular 1 to 11wt. %, particularly preferably 1 to 8 wt. %. Preferably, theconcentration in the casing is between 1 wt. % and 3 wt. %, and theconcentration in the core is at least 0.5 wt. % higher, particularlypreferably between 1.5 wt. % and 8 wt. %.

In this case, d-limonene can be included as a perfume component. In aparticularly preferred embodiment, the toilet cleansing block accordingto the invention includes a perfume made up of ethereal oils (alsoreferred to as essential oils). For example pine, citrus, jasmine,patchouli, rose, or ylang-ylang oil can be used as said oils within themeaning of the invention. Clary sage oil, chamomile oil, lavender oil,clove oil, melissa oil, mint oil, cinnamon leaf oil, lime blossom oil,juniper berry oil, vetiver oil, olibanum oil, galbanum oil, and labdanumoil, as well as orange blossom oil, neroli oil, orange peel oil, andsandalwood oil are also suitable.

In order to be perceptible, an odorant should be volatile, whereby inaddition to the nature of the functional groups and the structure of thechemical compound, the molar mass also plays an important role.Therefore, most odorants possess molar masses of up to approximately 200daltons, whereas molar masses of 300 daltons and above representsomething of an exception. Due to the differing volatility of odorants,the odor of a perfume composed of multiple odorants varies over thecourse of vaporization, the odor impressions being divided into “topnote”, “middle note or body” and “end note or dry out.”

Examples of semisolid odorants that can advantageously be used in theperfume oils within the scope of the present invention are essentialoils such as angelica root oil, anise oil, arnica blossom oil, basiloil, bay oil, champaca blossom oil, abies alba oil, abies alba cone oil,elemi oil, eucalyptus oil, fennel oil, spruce needle oil, galbanum oil,geranium oil, ginger grass oil, guaiac wood oil, gurjun balsam oil,helichrysum oil, ho oil, ginger oil, iris oil, cajeput oil, calamus oil,chamomile oil, camphor oil, cananga oil, cardamom oil, cassia oil, pineneedle oil, copaiba balsam oil, coriander oil, spearmint oil, carawayoil, cumin oil, lemon grass oil, musk seed oil, myrrh oil, clove oil,neroli oil, niaouli oil, olibanum oil, oregano oil, palmarosa oil,patchouli oil, balsam Peru oil, petitgrain oil, pepper oil, peppermintoil, allspice oil, pine oil, rose oil, rosemary oil, sandalwood oil,celery oil, star anise oil, thuja oil, thyme oil, verbena oil, vetiveroil, juniper berry oil, wormwood oil, wintergreen oil, ylang-ylang oil,hyssop oil, cinnamon oil, cinnamon leaf oil and cypress oil.

However, higher-boiling and solid odorants of natural or syntheticorigin may also advantageously be used in the perfume oils, within thescope of the present invention, as semisolid odorants or odorantmixtures. These compounds include the compounds described below andmixtures thereof: Ambrettolide, α-amylcinnamaldehyde, anethole,anisaldehyde, anise alcohol, anisole, anthranilic acid methyl ester,acetophenone, benzyl acetone, benzaldehyde, benzoic acid ethyl ester,benzophenone, benzyl alcohol, borneol, benzyl acetate, α-bromostyrene,n-decyl aldehyde, n-dodecyl aldehyde, eugenol, eugenol methyl ether,eucalyptol, farnesol, fenchone, fenchyl acetate, geranyl acetate,geranyl formate, heliotropin, heptyne carboxylic acid methyl ester,heptaldehyde, hydroquinone dimethyl ether, hydroxycinnamaldehyde,hydroxycinnamyl alcohol, indole, irone, isoeugenol, isoeugenol methylether, isosafrole, jasmone, camphor, carvacrol, carvone, p-cresol methylether, coumarin, p-methoxyacetophenone, methyl n-amyl ketone, methylanthranilic acid methyl ester, p-methyl acetophenone, methyl chavicol,p-methyl quinoline, methyl β-naphthyl ketone, methyl n-nonylacetaldehyde, methyl n-nonyl ketone, muscone, β-naphthol ethyl ether,β-naphthol methyl ether, nerol, nitrobenzene, n-nonyl aldehyde, nonylalcohol, n-octyl aldehyde, p-oxyacetophenone, pentadecanolide, β-phenylethyl alcohol, phenyl acetaldehyde dimethyl acetal, phenylacetic acid,pulegone, safrole, salicylic acid isoamyl ester, salicylic acid methylester, salicylic acid hexyl ester, salicylic acid cyclohexyl ester,santalol, skatole, terpineol, thymene, thymol, γ-undecalactone,vanillin, veratrum aldehyde, cinnamaldehyde, cinnamyl alcohol, cinnamicacid, cinnamic acid ethyl ester, and cinnamic acid benzyl ester.

More volatile odorants that can advantageously be used in the perfumeoils within the scope of the present invention include in particularlower-boiling odorants of natural or synthetic origin, which may be usedalone or in mixtures. Examples of more volatile odorants are alkylisothiocyanates (alkyl mustard oils), butanedione, limonene, linalool,linayl acetate and propionate, menthol, menthone, methyl-n-heptenone,phellandrene, phenylacetaldehyde, terpinyl acetate, citral andcitronellal.

Surfactants

The toilet rim block according to the invention includes at least onenon-ionic surfactant, a C₁₂₋₂₂ fatty alcohol alkoxylate having a degreeof ethoxylation of from 12 to 28 being included, as well as at least onealkylbenzene sulfonate and at least one olefin sulfonate. Said block canin addition include further surfactants.

Preferred alkylbenzene sulfonates are in particular those havingapproximately 12 C-atoms in the alkyl moiety, such as linear sodiumC10-13 alkylbenzene sulfonate. Preferred olefin sulfonates have a carbonchain length of from 14 to 16. The toilet cleansing block according tothe invention preferably includes from 10 to 70 wt. %, preferably 20 to65 wt. %, particularly preferably 20 to 30 wt. % alkylbenzene sulfonate,and preferably 10 to 30 wt. %, preferably 15 to 30 wt. %, particularlypreferably 15 to 25 wt. % olefin sulfonate.

Non-Ionic Surfactants

Further non-ionic surfactants can be included in addition to the C₁₂₋₂₂fatty alcohol alkoxylate having a degree of ethoxylation of from 12 to28. Further suitable non-ionic surfactants within the scope of theinvention can be alkoxylates, such as polyglycol ethers, fatty alcoholpolyglycol ethers, alkylphenol polyglycol ethers, end-capped polyglycolethers, mixed ethers and hydroxy mixed ethers and fatty acid polyglycolesters. Ethylene oxide/propylene oxide block copolymers, fatty acidalkanolamides and fatty acid polyglycol ethers can also be used. Afurther significant class of non-ionic surfactants that can be usedaccording to the invention are the polyol surfactants and here inparticular the glycol surfactants such as alkyl polyglycosides and fattyacid glucamides. The alkyl polyglycosides are particularly preferred, inparticular the alkyl polyglucosides, and above all the fatty alcoholalkoxylates (fatty alcohol polyglycol ethers).

Preferred fatty alcohol alkoxylates are ethylene oxide (EO) and/orpropylene oxide (PO)-alkoxylated, unbranched or branched, saturated orunsaturated C₈₋₂₂ alcohols having a degree of alkoxylation of up to 30,preferably ethoxylated C₁₂₋₂₂ fatty alcohol having a degree ofethoxylation of less than 30, preferably 12 to 28, in particular 20 to28, particularly preferably 25, for example C₁₆₋₁₈ fatty alcoholethoxylates having 25 EO.

Alkly polyglycosides are surfactants that can be obtained by reactingsugars and alcohols according to the relevant methods of preparativeorganic chemistry, the mixture being one of monalkylated, oligomeric orpolymeric sugars, depending on the type of production. The alkylpolyglucosides are preferred alkyl polyglycosides, the alcoholparticularly preferably being a long-chain fatty alcohol or a mixture oflong-chain fatty alcohols and branched or unbranched C₈ to C₁₈ alkylchains and the degree of oligomerization (DP) of the sugars beingbetween 1 and 10, preferably 1 to 6, in particular 1.1 to 3, mostpreferably 1.1 to 1.7, for example C₈₋₁₀ alkyl-1.5-glucoside (DP of1.5).

Fatty alcohol ethoxylates are preferably used in amounts of up to 20 wt.%, particularly preferably 4 to 12 wt. %, particularly preferably 7 to 9wt. %. In addition, further non-ionic surfactants such as fatty acidmonoalkanolamides and/or alkyl polyglycosides can be included in amountsof up to 10 wt. %.

Further Anionic Surfactants

The toilet rim block according to the invention can include aliphaticsulfates such as fatty alcohol sulfates, fatty alcohol ether sulfates,dialkyl ether sulfates, monoglyceride sulfates and aliphatic sulfonatessuch as alkane sulfonates, ether sulfonates, n-alkyl ether sulfonates,ester sulfonates and lignosulfonates as further anionic surfactants.Fatty acid cyanamides, sulfosuccinates (sulfosuccinic acid esters), inparticular sulfosuccinic acid mono- and di-C₈-C₁₈-alkyl esters,sulfosuccinamates, sulfosuccinamides, fatty acid isethionates,acylaminoalkansulfonates (fatty acid taurides), fatty acid sarcosinates,ether carboxylic acids and alkyl(ether)phosphates, and a-sulfo fattyacid salts, acylglutamates, monoglyceride disulfates and alkyl ethers ofglycerol disulfate can also be used within the scope of the presentinvention.

The fatty alcohol sulfates and/or fatty alcohol ether sulfates, inparticular the fatty alcohol sulfates, are preferred within the scope ofthe present invention. Fatty alcohol sulfates are products of sulfationreactions on corresponding alcohols, while fatty alcohol ether sulfatesare products of sulfation reactions on alkoxylated alcohols. A personskilled in the art generally understands alkoxylated alcohols to be thereaction products of alkylene oxide, preferably ethylene oxide, withalcohols, within the meaning of the invention preferably with long-chainalcohols. In general, n mol ethylene oxide and one mol alcohol results,depending on the reaction conditions, in a complex mixture of additionproducts having different degrees of ethoxylation. A further embodimentof the alkoxylation consists in using mixtures of the alkylene oxides,preferably the mixture of ethylene oxide and propylene oxide. Thesulfates of low-ethoxylated fatty alcohols having from 1 to 4 ethyleneoxide units (EO), in particular 1 to 2 EO, for example 1.3 EO, arepreferred fatty alcohol ether sulfates.

The anionic surfactants are preferably used as sodium salts, but canalso be included as other alkali or alkaline-earth metal salts, forexample magnesium salts, and in the form of ammonium salts or mono-,di-, tri- or tetraalkylammonium salts, and in the case of thesulfonates, also in the form of their corresponding acids, e.g.dodecylbenzenesulfonic acid.

In addition to the types of surfactants mentioned thus far, the agentaccording to the invention can in addition also include cationicsurfactants and/or amphoteric surfactants.

Suitable amphoteric surfactants are, for example, betaines of formula(R^(iii))(R^(iv))(R^(v))N⁺CH₂COO⁻, in which denotes an alkyl functionalgroup, which is optionally interrupted by heteroatoms or heteroatomgroups, having 8 to 25, preferably 10 to 21, carbon atoms, and R^(iv)and R^(v) denote identical or different alkyl functional groups having 1to 3 carbon atoms, in particular C₁₀-C₁₈ alkyl dimethyl carboxymethylbetaine and C₁₁-C₁₇ alkyl amido propyl dimethyl carboxymethyl betaine.

Suitable cationic surfactants are, inter alia, the quaternary ammoniumcompounds of formula (R^(vi))(R^(vii))(R^(viii))(R^(ix))N⁺X⁻, in whichR^(vi) to R^(ix) denote four identical or different, and in particulartwo long-chain and two short-chain, alkyl functional groups, and X⁻denotes an anion, in particular a halide ion, for example didecyldimethyl ammonium chloride, alkyl benzyl didecyl ammonium chloride andthe mixtures thereof.

Further Ingredients

In addition to the components mentioned thus far, the toilet rim blockaccording to the invention can include further ingredients that areusually used in toilet rim blocks, preferably selected from the groupcomprising acids, bases, salts, thickening agents, antimicrobial activeingredients, preservatives, complexing agents, polymers, dyes,fragrances, perfume boosters, fillers, builders, bleaching agents,corrosion inhibitors, rinsing regulators, enzymes, microorganisms,active ingredients for inhibiting limescale deposits, active ingredientsfor reducing dirt adhesion, active ingredients for improvingworkability, active ingredients for reducing adhesiveness, and mixturesthereof. Overall, no more than 60 wt. %, preferably 0.01 to 60 wt. %, inparticular 0.2 to 15 wt. % further ingredients should be included.

Acids

Toilet rim blocks according to the invention can include one or moreacids and/or the salts thereof in order to increase the power forcleaning limescale and urine deposits. The acids are preferably producedfrom sustainable raw materials. Therefore, in particular organic acidssuch as formic acid, acetic acid, citric acid, glycolic acid, lacticacid, succinic acid, adipic acid, malic acid, tartaric acid and gluconicacid, and mixtures thereof, are suitable as acids. In addition, however,the inorganic acids hydrochloric acid, sulfuric acid, phosphoric acidand nitric acid, or sulfamic acid and the mixtures thereof can also beused. The acids and/or the salts thereof selected from the groupcomprising citric acid, lactic acid, formic acid, the salts thereof, andmixtures thereof are particularly preferred. Said acids and/or salts areused in amounts of from 0.01 to 10 wt. %, particularly preferably 0.2 to5 wt. %.

In a preferred embodiment, the composition in addition includesinorganic salts, preferably alkali- or alkaline-earth metal salts, inparticular carbonates, sulfates, halides or phosphates, and mixturesthereof. Particularly preferably, sodium sulfate and/or sodium carbonateare used. In this case, sodium sulfate can be included in an amount ofup to 60 wt. %, preferably from 0.01 to 60 wt. %, particularlypreferably 20 to 60 wt. %, in particular 35 to 55 wt. %. Sodiumcarbonate and further salts can be included in an amount of up to 30 wt.%, preferably up to 10 wt. %, particularly preferably up to 5 wt. %.

Bases

Further alkalis can be included in compositions according to theinvention. Bases from the group of the alkali- and alkaline-earth metalhydroxides and carbonates, in particular sodium carbonate or sodiumhydroxide, are preferably used as bases in the compositions according tothe invention. In addition, however, ammonia and/or alkanolamines havingup to 9 C-atoms in the molecule, preferably the ethanolamines, inparticular monoethanolamine, can also be used.

Antimicrobial Active Ingredients

Disinfection and sanitation are a particular form of cleaning. In acorresponding particular embodiment of the invention, the toiletcleansing block therefore includes one or more antimicrobial activeingredients, preferably in an amount of from 0.01 to 1 wt. %, preferably0.02 to 0.8 wt. %, in particular 0.05 to 0.5 wt. %, particularlypreferably 0.1 to 0.3 wt. %, most preferably 0.2 wt. %.

The terms “disinfection”, “sanitation”, “antimicrobial effect” and“antimicrobial active ingredient” have the conventional meaning thereofwithin the scope of the teaching according to the invention. Whereasdisinfection, in the narrow sense, means the medical practice ofkilling, theoretically all, infection germs, sanitation is to beunderstood as eliminating, as far as possible all, germs, includingsaprophytic germs that are usually harmless to humans. In this case, theextent of the disinfection or sanitation depends on the antimicrobialeffect of the composition used, which effect reduces as the content ofantimicrobial active ingredient decreases or as the composition to beused becomes increasingly diluted.

For example antimicrobial active ingredients from the groups of thealcohols, aldehydes, antimicrobial acids and the salts thereof,carboxylic acid esters, acid amides, phenols, phenol derivatives,diphenyls, diphenyl alkanes, urea derivatives, oxygen and nitrogenacetals and methylals, benzamidines, isothiazoles and the derivativesthereof such as isothiazolins and isothiazolinones, phthalimidederivatives, pyridine derivatives, antimicrobial surface-activecompounds, guanidines, antimicrobial amphoteric compounds, quinolines,1,2-Dibromo-2,4-dicyanobutane, iodo-2-propynyl-butylcarbamate, iodine,iodophors, compounds that lose active chlorine, and peroxides aresuitable according to the invention. Preferred antimicrobial activeingredients are preferably selected from the group comprising ethanol,n-propanol, i-propanol, 1,3-butanediol, phenoxyethanol, 1,2-propyleneglycol, glycerol, undecylenic acid, citric acid, lactic acid, benzoicacid, salicylic acid, thymol, 2-Benzyl-4-chlorophenol,2,2′-methylenebis(6-bromo-4-chlorophenol),2,4,4′-trichloro-2′-hydroxydiphenyl ether,N-(4-chlorophenyl)-N′-(3,4-dichlorophenyl)urea,N,N′-(decane-1,10-diyldi-1-pyridyl-4-ylidene)bis(octylammonium)dichloride,N,N-bis(4-chlorophenyl)3,12-diimino-2,4,11,13-tetraazatetradecandiimidamide,antimicrobial quaternary surface-active compounds, guanidines and sodiumdichloroisocyanurate (DCI, 1,3-dichloro-5H-1,3,5-triazine-2,4,6-trionesodium salt). Preferred antimicrobially acting surface-active quaternarycompounds include an ammonium, sulfonium, phosphonium, iodonium orarsonium group. Furthermore, antimicrobially acting essential oils canalso be used, which oils simultaneously fragrance the cleaning agent.Particularly preferred antimicrobial active ingredients are, however,selected from the group comprising salicylic acid, quaternarysurfactants, in particular benzalkonium chloride, peroxo compounds, inparticular hydrogen peroxide, alkali metal hypochlorite, sodiumdichloroisocyanurate and mixtures thereof.

Preservatives

Toilet cleansing blocks according to the invention can also includepreservatives. Substantially the substances mentioned under theantimicrobial active ingredients can be used as preservatives of thiskind.

Complexing Agents

Complexing agents (INCI Chelating Agents), also referred to assequestering agents, are ingredients that allow metal ions to formcomplexes and to become inactive, in order to prevent thedisadvantageous effects of said ions on the stability or the appearanceof the agent, for example cloudiness. In this case it is important toform complexes from the calcium and magnesium ions of the water hardnessthat are incompatible with many ingredients. However, forming complexesfrom ions of heavy metals such as iron or copper slows the oxidativedecomposition of the finished agents. The complexing agents in additionassist the cleaning effect.

For example the following complexing agents, named in accordance withINCI, are suitable: Aminotrimethylene Phosphonic Acid, Beta-AlanineDiacetic Acid, Calcium Disodium EDTA, Citric Acid, Cyclodextrin,Cyclohexanediamine Tetraacetic Acid, Diammonium Citrate, DiammoniumEDTA, Diethylenetriamine Pentamethylene Phosphonic Acid, DipotassiumEDTA, Disodium Azacycloheptane Diphosphonate, Disodium EDTA, DisodiumPyrophosphate, EDTA, Etidronic Acid, Galactaric Acid, Gluconic Acid,Glucuronic Acid, HEDTA, Hydroxypropyl Cyclodextrin, Methyl Cyclodextrin,Pentapotassium Triphosphate, Pentasodium Aminotrimethylene Phosphonate,Pentasodium Ethylenediamine Tetramethylene Phosphonate, PentasodiumPentetate, Pentasodium Triphosphate, Pentetic Acid, Phytic Acid,Potassium Citrate, Potassium EDTMP, Potassium Gluconate, PotassiumPolyphosphate, Potassium Trisphosphonomethylamine Oxide, Ribonic Acid,Sodium Chitosan Methylene Phosphonate, Sodium Citrate, SodiumDiethylenetriamine Pentamethylene Phosphonate, SodiumDihydroxyethylglycinate, Sodium EDTMP, Sodium Gluceptate, SodiumGluconate, Sodium Glycereth-1 Polyphosphate, Sodium Hexametaphosphate,Sodium Metaphosphate, Sodium Metasilicate, Sodium Phytate, SodiumPolydimethylglycinophenolsulfonate, Sodium Trimetaphosphate, TEA-EDTA,TEA-Polyphosphate, Tetrahydroxyethyl Ethylenediamine, TetrahydroxypropylEthylenediamine, Tetrapotassium Etidronate, TetrapotassiumPyrophosphate, Tetrasodium EDTA, Tetrasodium Etidronate, TetrasodiumPyrophosphate, Tripotassium EDTA, Trisodium Dicarboxymethyl Alaninate,Trisodium EDTA, Trisodium HEDTA, Trisodium NTA and Trisodium Phosphate.

Polymers

The toilet rim block according to the invention can additionally includepolymers. Said polymers can, for example, reduce calcification and thetendency to become resoiled.

Acrylic polymers, such as are commercially available from the companyRhodia under the trade name Mirapol, are preferred polymers in thiscase.

Fragrances and Dyes

The toilet rim block according to the invention can include one or morefragrances and/or one or more dyes (INCI Colorants) as furtheringredients. In this case, both water-soluble and oil-soluble dyes canbe used as dyes, it being important both to take into account thecompatibility with further ingredients, for example bleaching agents,and that the dye used should not significantly affect the toiletceramics, even after long-term use. The dyes are preferably included inan amount of from 0.0001 to 0.1 wt. %, in particular 0.0005 to 0.05 wt.%, particularly preferably 0.001 to 0.01 wt. %.

Builders

Water-soluble and/or water-insoluble builders can optionally be used inthe toilet rim block according to the invention. In this case,water-soluble builders are preferred since they are generally lesslikely to form insoluble residues on hard surfaces. Conventionalbuilders which may be added within the scope of the invention arelow-molecular polycarboxylic acids and the salts thereof, homopolymericand copolymeric polycarboxylic acids and the salts thereof, citric acidand the salts thereof, carbonates phosphates and silicates. The categoryof water-insoluble builders includes zeolites, which may also be used,as well as mixtures of the aforementioned builder substances.

Bleaching Agents

According to the invention bleaching agents can be added to the cleaningagent. Suitable bleaching agents include peroxides, peroxy acids and/orperborates, hydrogen peroxide being particularly preferred. In contrast,sodium hypochlorite is less suitable in the case of cleaning agentshaving an acidic formulation, on account of the release of poisonouschlorine gas vapor, but can be used in the case of alkaline cleaningagents. In some circumstances, a bleach activator may also be requiredin addition to the bleaching agent.

Corrosion Inhibitors

Suitable corrosion inhibitors are, for example, the followingsubstances, named in accordance with INCI: Cyclohexylamine, DiammoniumPhosphate, Dilithium Oxalate, Dimethylamino Methylpropanol, DipotassiumOxalate, Dipotassium Phosphate, Disodium Phosphate, DisodiumPyrophosphate, Disodium Tetrapropenyl Succinate, HexoxyethylDiethylammonium, Phosphate, Nitromethane, Potassium Silicate, SodiumAluminate, Sodium Hexametaphosphate, Sodium Metasilicate, SodiumMolybdate, Sodium Nitrite, Sodium Oxalate, Sodium Silicate,Stearamidopropyl Dimethicone, Tetrapotassium Pyrophosphate, TetrasodiumPyrophosphate, Triisopropanolamine.

Rinsing Regulators

The substances referred to as rinsing regulators primarily control theconsumption of the composition during use such that the intended servicelife is met. Solid long-chain fatty acids such as stearic acid, but alsosalts of such fatty acids, fatty acid ethanolamides such as coconutfatty acid monoethanolamide, or solid polyethylene glycols such as thosehaving molecular weights of between 10000 and 50000 are preferablysuitable as regulators.

Active Ingredients for Reducing Adhesiveness

In order to improve the workability when producing the toilet rim blockaccording to the invention, an active ingredient can be used to reducethe adhesiveness. Thus, adding dolomite powder or titanium dioxidepowder having a fine particle size distribution improves the workingbehavior when forming balls and significantly reduces wear andadhesiveness.

The results using active ingredients of this kind are better than usingother conventional measures, such as coating the balls with a slidingagent, powdering or coating the section rolls with Teflon.

Enzymes

The composition can also include enzymes, preferably proteases, lipases,amylases, hydrolases and/or cellulases. Said enzymes can be added to thecomposition according to the invention in any enzyme form established inthe prior art. These include solutions of the enzymes, advantageously asconcentrated as possible, dry and/or mixed with stabilizers.Alternatively the enzymes can also be encapsulated, for example throughspray-drying or extrusion of the enzyme solution together with apreferably natural polymer or in the form of capsules, for example thosein which the enzymes are enclosed in a set gel, or in those of thecore-shell type in which an enzyme-containing core is coated with awater-, air-, and/or chemical-impermeable protective layer. In the caseof overlaid layers, other active ingredients, such as stabilizers,emulsifiers, pigments, bleaching agents, or dyes, can be additionallyapplied. Such capsules are applied using inherently known methods, forexample through shaking or roll granulation or in fluidized bedprocesses. Such granulates are advantageously low in dust, for exampledue to the application of polymeric film-formers, and stable in storagedue to the coating.

Furthermore, enzyme stabilizers can be present in enzyme-containingcompositions in order to protect an enzyme included in a compositionaccording to the invention against damage, for example inactivation,denaturation, or decomposition caused, for example, by physicalinfluences, oxidation, or proteolytic cleavage. Depending in each caseon the enzyme used, particularly suitable enzyme stabilizers are:benzamidine hydrochloride, borax, boric acid, boronic acid or the saltsor esters thereof, in particular derivatives having aromatic groups,such as substituted phenylboronic acids or the salts or esters thereof;peptide aldehydes (oligopeptides having a reduced C-terminus),alkanolamines such as mono-, di- and tri-ethanol and -propanolamine andthe mixtures thereof, aliphatic carboxylic acids up to C₁₂, such assuccinic acid, other dicarboxylic acids or salts of the mentioned acids;end-capped fatty acid amide alkoxylates; low aliphatic alcohols and inparticular polyols, for example glycerol, ethylene glycol, propyleneglycol or sorbitol; and reducing agents and antioxidants such as sodiumsulfite and reducing sugars. Further suitable stabilizers are known fromthe prior art. Preferably, combinations of stabilizers are used, forexample the combination of polyols, boric acid and/or borax, thecombination of boric acid or borate, reducing salts and succinic acid orother dicarboxylic acids, or the combination of boric acid or boratewith polyols or polyamino compounds and with reducing salts.

In a particularly preferred embodiment of the invention, the core andcasing are different colors. Furthermore, particularly preferably, thecore and casing are each a homogenous color. The color differencebetween the color of the casing and of the core (ΔE*_(ab)) is preferablygreater than 3 in the CIE 1976 (L, a*, b*) color coordinate system.

ΔE* _(ab)=√{square root over (*L* ₂ −L* ₁)²+(a* ₂ −a* ₁)²+(b* ₂ −b*₁)²)}

Alternatively or in addition, it is preferable for at least one color,preferably both, of the core and the casing to have a colorfulness(chroma) of between 20% and 99%, preferably between 30% and 95%.

Individually or preferably combined, the color settings according to theinvention significantly improve the ability of the user of the toiletrim block to identify the degree of consumption. This is because themutually contrasting effect of the elements make observation easier.

In an alternative variant of the invention, the color difference betweenthe color of the casing and of the core (ΔE*_(ab)) is preferably lessthan 10, preferably less than 3, in the CIE 1976 (L, a*, b*) colorcoordinate system. In this case, it is preferable for the core to havedifferent active ingredients and/or a different concentration of thesame active ingredient compared to the casing. The user does not noticewhen the casing has been used up, and can have the impression that thetoilet rim block consists of a single active ingredient composition.Nonetheless, a changed active ingredient composition of the core can atleast in part compensate for the functionality and the effect, forexample, of the toilet rim block in the event of heavy wear.

In the present description, the color features relate to the CIE 1976color coordinate system. If an illuminant is required, the D65, or anapproximation thereof that can be used in the conventional manner, isused.

The present invention also provides a device that comprises a toilet rimblock as described herein, and a retaining means for holding the toiletrim block on the toilet bowl. The device is preferably a rim block cage.

Rim Block Cage

According to the invention a rim block cage is provided, comprising atleast one toilet rim block according to the invention. The rim blockcage can preferably also comprise at least two, particularly preferablyat least three toilet rim blocks according to the invention. The toiletrim blocks each comprise at least one polar cap and are arrangedtogether in a regular or irregular manner. The irregular arrangement ispreferred on account of the simpler production method. The regulararrangement is also significant, however, in particular on account ofthe aesthetic form, in particular if the pole and casing are differentcolors. The toilet rim blocks of the rim block cage are preferablyrotationally symmetrical, more preferably spherical.

The rim block cage according to the invention is suitable for dispensingcompositions into a toilet bowl. Said cage comprises a receptacle thatis to be arranged in the toilet bowl, it being possible to fasten thereceptacle to the toilet bowl. The receptacle comprises a first chamberthat receives at least one toilet rim block. The receptacle preferablyfurther comprises a second chamber that receives a second toilet rimblock. Preferably at least one, preferably all, of the toilet rim blocksare separated from the base of the chambers by supporting means. Atleast one, preferably all, of the chambers in each case dispense thecompositions into the toilet bowl when flushing water flows over orthrough said chambers. The rim block cage is designed such that, whenflushing water flows thereover, the flushing water also comes intocontact with the toilet rim block, and the flushing water enriched withactive ingredient preparation can emerge from the rim block cage. Forexample inlet and outlet openings, water distribution elements and othermeans can be provided for this purpose. Embodiments will be describedwith reference to the drawings.

The rim block cage comprising the toilet rim block(s) is preferablyclosed such that it cannot be opened. It is thus not possible to reachthe toilet rim block(s) without applying significant force and deformingthe rim block cage.

The rim block cage is preferably transparent. A user can thus identifynot only the color but also the shape of the toilet rim block.

BRIEF DESCRIPTION OF THE DRAWINGS List of Figures

FIG. 1 is a plan view of the pole of a toilet rim block according to theinvention.

FIG. 2 is a side view of a toilet rim block according to the invention.

FIG. 3 shows a cross section of the toilet rim block from FIG. 2 in thedirection A-A.

FIG. 4 shows a cross section of the toilet rim block from FIG. 2 in thedirection B-B.

FIG. 5 is a cross-sectional view of the pressing process before andafter pressing.

FIG. 6 shows a cross section of a rim block cage comprising 3 toilet rimblocks.

DETAILED DESCRIPTION OF THE INVENTION

In a particularly preferred embodiment, the toilet rim block 1 comprisesthe casing 2 and the core 3. The core 3 forms a pole 4 which is visiblein the plan view according to FIG. 1. The first pole 4 and the secondpole 5 are visible in the side view according to FIG. 2. The core 3 issurrounded by the casing 2. The casing 2 is annular, as can be seen inthe cross-sectional view A-A having an approximately elliptical crosssection for example, and in the cross-sectional view B-B as a circularring. The pole 4 and/or the pole 5 can be more or less pronounced ineach case. This allows predefined, controlled release of activeingredients over the temporal progression. The diameter of the segment 6can also be smaller or larger. Instead of a cylindrical portion of thesegment 6, said segment can also have a different geometry.

Comparative Example

Toilet rim blocks were produced having the following compositions andused as reference:

E1 C₁₀₋₁₃ lin. Alkylbenzene sulfonate-Na 26 Fatty alcohol sulfate-Na —C₁₂ fatty alcohol sulfate-Na − C₁₄₋₁₆ olefin sulfonate-Na 18 C₁₆₋₁₈fatty alcohol ethoxylate 25 EO  8 Cellulose — Trisodium citratedihydrate  1 Sodium sulfate to make Sodium carbonate — C₁₂₋₁₈ fatty acidmonoethanolamide — Sodium silicate — Perfume   4.5 Dye +

The perfume composition used was composed as follows:

Dosage Wt. % Name CAS no. 12.16 dipropylene glycol 25265-71-8 8.51dihydromyrcenol 18479-58-8 7.30 terpineol 8000-41-7 4.86 linalyl acetate115-95-7 3.65 lemon oil messina 84929-31-7 3.65 agrunitrile 51566-62-23.65 orange oil sweet, Ital. 8028-48-6 3.65 otbcha 88-41-5 3.65styrallyl acetate 93-92-5 3.65 linalool 78-70-6 2.43 aldehyde c-08124-13-0 2.43 alcohol c-08 111-87-5 2.43 allyl amyl glycolate 67634-00-82.43 benzyl acetate 140-11-4 2.43 hedione 24851-98-7 1.52 linalool oxide1365-19-1 1.52 lemonile 61792-11-8 1.52 bromelia 93-18-5 1.52 yara yara93-04-9 1.52 aldehyde c-10 112-31-2 1.51 aldehyde c-14 (so-called)104-67-6 1.50 benzyl acetone 2550-26-7 1.50 acedyl 54830-99-8 1.50propidyl 68912-13-0 1.50 isobornyl acetate 125-12-2 1.50 terpinolene 30586-62-9 1.50 lilial, lysmeral 80-54-6 1.50 citronellol pure 106-22-91.50 geraniol pure 106-24-1 1.50 nerol standard 106-25-2 1.50 phenethylalcohol 60-12-8 1.50 geranyl acetate 16409-44-2 1.50 hexylcinnamaldehyde (alpha) 101-86-0 1.50 isoraldeine 70 1335-46-2 1.50beta-ionone synth. 14901-07-6 1.50 iso e super 54464-57-2 1.50 ethylenebrassylate 105-95-3

The composition was mixed, subsequently extruded to form a strand, cut,and shaped into balls in a forming die. The final diameter of every ballwas 25.4 mm.

Example

Toilet rim blocks according to the invention were produced as follows. Afirst composition A was provided, as in the reference example, the onlydifference being that the perfume concentration was changed from 4+/−0.5to 5.5+/−0.5. A second composition B was provided, as in the referenceexample, the only difference being that the perfume concentration waschanged from 4+/−0.5 to 2.5+/−0.5. As in the comparative example, thecompositions were in each case mixed. The mixture was then extruded toform a coaxial strand, comprising composition A as the inner strand andcomposition B as the outer strand. An extruder was used for thispurpose. The coaxial, cylindrical strands had an outer diameter of 20.5mm and an inner strand diameter of 7.3 mm. The strand was cut intocylinders of 26.36 mm in length, the cylinders each being shaped into aball. The final diameter of every ball was 25.4 mm.

Comparative Tests

Balls from the example and from the comparative example were used inidentical rim block cages and flushed in a test chamber in each case.The test chambers have an identical structure and are separated from oneanother so that there is no exchange of air between the chambers. Eachtest chamber additionally comprises a toilet bowl, and is rinsed by aconstant airflow. The test chambers are located in a space (measuringspace) specifically designed for the test chambers, which space isodorless, can be ventilated well and can optionally be subjected toforced ventilation by means of an activated carbon filter. The volumefraction of carbon dioxide in the measuring space is less than 0.15 vol.%, the air exchange rate is at least 4.4 m³/h per person. Thetemperature in the measuring space is 20° C. and is constant duringmeasuring. The measuring space is not exposed to any direct solarradiation, and other interfering sources of light and noise areminimized as far as possible. All the devices that are associated withthe test chamber must be odorless. The odor intensity is assessed by atleast 20 testers, with generally equal numbers of men and women, trainedin odors, being employed, who are all at least 16 years old. At the timethe compounds are assessed, the testers are not influenced byinterfering factors such as contact with perfumes, food, other naturalstimulants or by colds or allergies.

The rim block cages were hung in identical positions in the toiletbowls, and each toilet bowl was flushed out a times per hour. Each flushused 6 liters of water. The testers made the measurements at 4, 72, 96,120, 144, 168 and 172 hours. To carry out the assessment, the testeropens the window, positions their head in the interior of the testchamber, carries out the smell test, withdraws their head again and thencloses the window.

The testers had the clear impression that the fragrance strength of theexample according to the invention was greater than in the comparativeexample. The user perceives that the fragrance has increased, comparedto the comparative example, after just 72 hours. Since the core wasexposed, the initial difference from the comparative example was small;at the start the user perceived a loss of just 24%, but this was made upfor surprisingly quickly. Surprisingly, the user results were such thatthe toilet rim blocks and rim block cages according to the inventionemitted a stronger fragrance than the reference over the entire usagetime, although the amount of perfume used is identical.

The essential part of the method according to the invention is shown, incross section, in FIG. 5. A co-extruded strand portion 7 is placed in apress 8. The final shape of the press 8 is a ball having an identicalvolume to the strand portion 7. The strand portion is shaped into a ballaccording to the invention by the cavities of the press 8 being broughttogether and the final shape thus being achieved.

FIG. 6 shows a rim block cage, by way of example, in accordance with theinvention. FIG. 6 shows 3 toilet rim blocks that each comprise a casing2 and a pole 3. The toilet rim blocks are shown in the rim block cagethat is shown from the front, by dashed lines and comprising a hanger.The cage is shown schematically so that the toilet rim blocks are moreclearly visible. The toilet rim blocks are arranged in an irregularmanner relative to one another, since each pole 4 faces in a differentdirection.

What is claimed is:
 1. A toilet rim block comprising, at least a casingand a core, the casing comprising a first composition and the corecomprising a second composition, the first and the second compositiondiffering by at least one of the following features: different activeingredients, different concentration of the same active ingredient,different viscosity; the casing surrounding the core in part, the coreprojecting on at least one side of the toilet rim block, as a firstpole, as far as the surface, thus being exposed on a face, wherein theprofile of the core is such that the surface of the exposed face reduceswith uniform wear of the surface of the toilet rim block.
 2. The toiletrim block according to claim 1, wherein the toilet rim block has an arearatio of exposed surface of the core to exposed surface of the casing isbetween 5% and 67%.
 3. The toilet rim block according to claim 1,wherein the toilet rim block has an area ratio of exposed surface of thecore to exposed surface of the casing is between 10% and 38%.
 4. Thetoilet rim block according to claim 1, wherein, when the toilet rimblock has been partially dissolved, an area ratio of exposed surface ofthe core to exposed surface of the casing is between 1:3 and 1:1.
 5. Thetoilet rim block according to claim 1, wherein at least one portion ofthe core is a cylindrical segment.
 6. The toilet rim block according toclaim 5, wherein the central portion of the core is a cylindricalsegment.
 7. The toilet rim block according to claim 1, wherein the coreincludes a second pole that projects to the surface on the side of thetoilet rim block opposite the first pole.
 8. The toilet rim blockaccording to claim 1, wherein the first pole and the second pole areconnected by a strand-like core.
 9. The toilet rim block according toclaim 7, wherein the cross-sectional profile of the core has across-sectional reduction between the first pole and the second pole.10. The toilet rim block according to claim 1, wherein the toilet rimblock is sphericial.
 11. The toilet rim block according to claim 1,wherein the casing surrounds the core in an annular manner.
 12. Thetoilet rim block according to claim 1, wherein the first and the secondcomposition differ by a different concentration of the same activeingredient, wherein the core has a concentration of an active ingredientthat is at least 0.5 wt. %.
 13. The toilet rim block according to claim1, wherein the first and the second composition differ by a differentconcentration of the same active ingredient, wherein the core has aconcentration of an active ingredient that is at least 1 wt. % to 10 wt.% higher.
 14. A rim block cage comprising at least two toilet rim blocksaccording to claim 1, wherein the toilet rim blocks are arranged in aregular or irregular manner relative to one another.
 15. The rim blockcage according to claim 14, wherein the toilet rim blocks arerotationally symmetrical.
 16. The rim block cage according to claim 14,wherein the toilet rim blocks are arranged in an irregular mannerrelative to one another.